Waterborne underbody coating system

Abstract

The present invention provides a water-based coating system that can be used to form a durable, abrasion resistant, tough, protective coating on a wide range of substrates, including the underbody of transport vehicles, storage units, and the like. The coating composition includes an asphaltic component and advantageously has excellent adhesion properties when coated onto metal surfaces, including the underbody of transport vehicles, storage units and the like. The coating system is particularly effective for protecting metal or metal-containing substrates forming the underbody of an intermodal cargo container. The resultant coatings are flexible and impact resistant.

What is claimed is: 
     
       1. A method of coating a cargo container, comprising:
 providing a cargo container, wherein at least a portion of an exposed surface of the cargo container comprises an underbody of metal or metal-reinforced wood; and 
 applying an aqueous coating system on at least the underbody, wherein the system comprises an asphaltic coating composition comprising
 about 10 to 70 wt% of asphaltic particles; 
 about 5 to 10 wt% stabilizer; 
 about 10 to 50 wt% filler; and 
 about 15 to 65 wt% aqueous carrier. 
 
 
     
     
       2. A coated article, comprising:
 a cargo container; wherein at least a portion of an exposed surface of the cargo container comprises an underbody of metal or metal-reinforced wood; and 
 an aqueous coating applied on at least the underbody, wherein the aqueous coating comprises an asphaltic coating composition comprising
 about 10 to 70 wt% of asphaltic particles; 
 about 5 to 10 wt% stabilizer; 
 about 10 to 50 wt% filler; and 
 about 15 to 65 wt% aqueous carrier. 
 
 
     
     
       3. The method of  claim 1 , wherein the asphaltic composition comprises a dispersion of the asphaltic particles in the aqueous carrier. 
     
     
       4. The method of  claim 1 , wherein the asphaltic composition further comprises a stabilizing agent selected from the group consisting of anionic stabilizers, cationic stabilizers, and mixtures thereof. 
     
     
       5. The method of  claim 1 , wherein the asphaltic composition further comprises one or more mineral fillers selected from the group consisting of finely ground silica, talc, slate, china clay, fuller's earth, bentonite, powdered contact clay, and mixtures thereof. 
     
     
       6. The method of  claim 1 , wherein the asphaltic composition comprises
 about 20 to 40 wt% of asphaltic particles; 
 about 5 to 10 wt% stabilizer; 
 about 25 to 35 wt% filler; and 
 about 30 to 50 wt% aqueous carrier. 
 
     
     
       7. The method of  claim 1 , wherein the underbody has a primer composition applied thereon. 
     
     
       8. The method of  claim 1 , wherein the asphaltic coating composition further comprises less than about 1 wt% solvent. 
     
     
       9. The method of  claim 1 , wherein the asphaltic coating composition comprises at least 40 wt% solids. 
     
     
       10. The method of  claim 1 , wherein the asphaltic coating composition has no more than about 4 wt% VOCs. 
     
     
       11. A cargo container made by the method of  claim 1 .